The present invention pertains to fence posts, in general, and more particularly to a top cap for a fence post used for a retaining wires in a trellis matrix.
Previously, many types of retaining devices have been used to provide an effective means of forming a wire matrix for growing vine crops. Many types of vine crops require support above the ground to enhance harvesting ability and to minimize damage due to moisture and ground-based detrimental and deleterious affects.
A search of prior art did not disclose any patents that possess the novelty of the instant invention, however the following U.S. patents are considered related:
U.S. Pat. No. 5,966,867 issued to Downer, et al., is for a cross arm which is used at orchards and grapevines to support trees or vines, and that is attached to a fence post that has ribs and outward protruding studs. The cross bar is attached to the post using a U-bolt that is positioned directly above one of the studs holding it securely in place.
Galbraith in U.S. Pat. No. 5,438,795 teaches a grapevine trellis system that incorporates support brackets that are in a xe2x80x9cZxe2x80x9d shape and are arranged and constructed to be alternately mounted on a post. The post may be a solid T-bar or metal-roll formed T-shaped post, or the invention may be mounted on conventional wooden posts or stakes.
Broyles in U.S. Pat. No. 4,965,961 discloses a trellis wire support assembly for use with metal grape stakes. The device has a wire support clip and a fastener which secures the clip to the grape stake. The clip is formed having a vertical securement portion with a clip shoulder that engages a mating stake shoulder. Wire support portions extend from the ends of the securement portion and are slotted to movably receive trellis wires. Slots are formed in the device so that the wires cannot be lifted out of the clip during the growing season. A method of adapting the metal grape stake to vertical trellising using the clip is also taught.
Coulson teaches in U.S. Pat. No. 4,329,811 an all metal grape stake that has an elongated upright member which is rolled, forming a v-shape with flanges on each edge. The stake also has a cross-arm in the structure of a metal strip which is bent over across the top of the upright member. A V-shaped bracket is mounted in the center of the cross-arm and receives the upper end of the upright member.
U.S. Pat. No. 4,223,872 issued to Boal is for a wire engager for use with a chain link fence that includes a hollow cylindrical member with a plurality of Z-shaped apertures in the wall of the cylindrical member. While Boal appears to provide a labor saving approach in construction of such fences, this solution is unsuitable for the requirements of a vineyard system where wires are strung in a co-planar matrix at or near the top of the stakes.
Roberts in U.S. Pat. No. 3,791,070 teaches a cross beam for grape stakes that includes a upper planar member supported by a housing member projecting therefrom. The housing member has a lower opening which is fitted on the top of a grape stake. A second planar member projects from the ends of the first planar member at an angle to the end of the housing, and ribs are positioned between the planar members for grasping grape wires. The invention is made of plastic which is rugged and durable. It should be noted that the cross beam of Roberts is nailed to the stake to secure it in position.
For background purposes and as indicative of the art to which the invention is related, reference may be made to the remaining cited U.S. Pat. No.3,411,754 issued to Fahrenholz
For many years it has been a common practice in the grape growing industry to use a wooden stake that is driven into the ground with a cross member nailed to the top of the stake for supporting wires that form a matrix for bracing the vines. In recent years, metal fence posts have replaced the wooden stakes for strength and durability. A problem has arisen that nails can no longer be used on the metal posts, therefore the need for some other type of attachment means is necessary to retain the wires on top of the metal posts. Therefore, the primary object of the invention is to use a metal post cap that simply slips over the top of the post, thus making it easy and simple to install with the device so configured as to fit a conventional xe2x80x9csoil setxe2x80x9d fence post configured in a xe2x80x9cTxe2x80x9d shape. Normally, this type of post has a series of studs on the surface, corresponding to the top of a xe2x80x9cTxe2x80x9d, which are used to tie barbed wire at horizontally spaced intervals. The invention uses the studs to position a top cap away from the front of the post enough to place a fastener in between, with the stud limiting the travel of the cap in an upward direction and the cap itself having a bent lip holding it in place on the top, thus preventing it from slipping down.
An important object of the invention is that the configuration of the top cap is designed such that, even if the top of the post is deformed or bent, the cap has enough spring to open sufficiently to still slide over the top with slight urging on part of the installer.
Another object of the invention is that during normal installation no tools are required and the device is small enough to allow a number of them to be carried together, thus making installation quick and easy. Further, when the cap is positioned over the post, it is locked in place with a cotter pin, which is inserted into mating holes that are located on the sides adjacent to the appropriate stud on the post. The outermost, extended end of the cotter pin is simply bent down by hand, with the other end left horizontal or bent upright as desired.
Still another object of the invention is that metal is used to fabricate the top cap. Prior art has employed thermoplastic as a material for top caps, however, in time the material deteriorates and breakage is common, thus limiting the life of the device. This limiting effect creates severe problems in replacement, as the vines are heavy and hang over the wires, thereby making it difficult to lift them and placing the wires high enough to replace the top cap as it slips over the entire top of the post. The use of metal, preferably steel, creates a long-lasting, durable cap that has the potential of lasting as long as the post itself The cap is further protected by the use of a galvanized plating which prevents corrosion. Additionally, the edges that are exposed after being cut and punched have a thin coat of zinc from the plating as the die wipes across the metal during the manufacturing process.
Yet another object of the invention is that the top cap""s material has no effect upon the environment as it is impervious to the elements and when no longer needed may be recycled as steel, which may be used for other purposes.
A further object of the invention is the ease of manufacturing since the cap is easily sheared to size, punched with holes and slots, and formed to shape all by common standard metal working equipment that is well known in the art and readily available. With this in mind, the cost impact of the top caps, relative to its life expectancy, makes their use cost effective.
A further object of the invention is in the design of the upper portion of the cap, which permits wires to be easily installed in any direction even on the side, with the extending upright angles, as the wire may be simply offset in the position required. The formed right angle lip on the top provides an ideal base for the wires and extends the surface of the post top, thus making a smooth platform for the wires which forms the matrix for vines to grip onto. The wires are easily retained from being lifted off of the top by the use of a simple cotter pin threaded though holes in the upright legs after the matrix is properly positioned.
These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompanying drawings.